Experiential contributions to social dominance in a rat model of fragile-X syndrome

Social withdrawal is one phenotypic feature of the monogenic neurodevelopmental disorder fragile-X. Using a 'knockout' rat model of fragile-X, we examined whether deletion of the Fmr1 gene that causes this condition would affect the ability to form and express a social hierarchy as measured in a tube test. Male fragile-X 'knockout' rats living together could successfully form a social dominance hierarchy, but were significantly subordinate to wild-type animals in mixed group cages. Over 10 days of repeated testing, the fragile-X mutant rats gradually showed greater variance and instability of rank during their tube-test encounters. This affected the outcome of future encounters with stranger animals from other cages, with the initial phenotype of wild-type dominance lost to a more complex picture that reflected, regardless of genotype, the prior experience of winning or losing. Our findings offer a novel insight into the complex dynamics of social interactions between laboratory living groups of fragile-X and wild-type rats. Even though this is a monogenic condition, experience has an impact upon future interactions with other animals. Gene/environment interactions should therefore be considered in the development of therapeutics.

Conventional fractionation should not be the standard of care for T2 glottic cancer

Background

The aim of this study was to report outcomes and late toxicity following hypofractionated accelerated radiotherapy for T2 glottic cancers. We highlight the importance of hypofractionated treatments with shorter overall treatment times, in improving outcomes for T2 glottic cancers. We also compare the biologically effective dose of hypofractionated regimes, with conventional fractionation.

Methods

One hundred twelve patients with T2 glottic cancer were treated between January 1999 and December 2005. All patients were prescribed a hypofractionated accelerated radiotherapy dose of 52.5 Gray in 3.28 Gray per fraction, delivered over 22 days. Radiobiological calculations were used to assess the relationship of fraction size and overall treatment time on local control outcomes and late toxicity.

Results

The 5-year overall survival was 67%, the 5-year local control was 82%, and the 5-year disease-specific survival was 90%. The respective 5-year local control for T2a and T2b disease was 88.8 and 70.8% (p = 0.032). Severe late toxicity occurred in two patients (1.8%). Radiobiological calculations showed an increase in local control of nearly 12%, with a 10 Gray increase in biologically effective dose.

Conclusion

This study has demonstrated that accelerated hypofractionated regimes have improved local control and similar late toxicity compared with conventional fractionation schedules. This supports the use of hypofractionated regimes as the standard of care for early glottic laryngeal cancers.

A clinical-scale BioArtificial Liver, developed for GMP, improved clinical parameters of liver function in porcine liver failure

Liver failure, whether arising directly from acute liver failure or from decompensated chronic liver disease is an increasing problem worldwide and results in many deaths. In the UK only 10% of individuals requiring a liver transplant receive one. Thus the need for alternative treatments is paramount. A BioArtificial Liver machine could temporarily replace the functions of the liver, buying time for the patient's liver to repair and regenerate. We have designed, implemented and tested a clinical-scale BioArtificial Liver machine containing a biomass derived from a hepatoblastoma cell-line cultured as three dimensional organoids, using a fluidised bed bioreactor, together with single-use bioprocessing equipment, with complete control of nutrient provision with feedback BioXpert recipe processes, and yielding good phenotypic liver functions. The methodology has been designed to meet specifications for GMP production, required for manufacture of advanced therapy medicinal products (ATMPs). In a porcine model of severe liver failure, damage was assured in all animals by surgical ischaemia in pigs with human sized livers (1.2-1.6 kg liver weights). The BioArtificial liver (UCLBAL) improved important prognostic clinical liver-related parameters, eg, a significant improvement in coagulation, reduction in vasopressor requirements, improvement in blood pH and in parameters of intracranial pressure (ICP) and oxygenation.

Ninety Day Mortality After Radical Radiotherapy for Head and Neck Cancer

AIMS

Treatment for head and neck cancers using definitive radiotherapy, with or without chemotherapy, is associated with significant acute toxicity. Our aim was to assess 90 day mortality after radical radiotherapy. A further aim was to identify patient, tumour or treatment factors associated with early death after treatment and whether these could be used to predict outcomes.

MATERIALS AND METHODS

In total, 1116 patients with squamous cell pharyngeal and larynx cancer between January 2011 and December 2015 were included. Patients with T1 larynx cancer were excluded. Patients were treated using radical radiotherapy, with or without chemotherapy. Ninety day mortality was calculated using survival of less than 135 days from the planned start date for radical radiotherapy, to include early deaths during and up to 90 days after treatment.

RESULTS

Overall, 90 day mortality was 4.7%. Among the subgroup of patients treated with concurrent platinum chemotherapy, the 90 day mortality rate was 0.4%. Overall survival at 1, 3 and 5 years was 84%, 62% and 53%, respectively. Factors associated with a higher risk of early death included performance status > 1, haemoglobin <100 g/l, weight < 60 kg, age > 80 years and presence of multiple comorbidities.

CONCLUSION

We report excellent crude overall survival rates among our radically treated cohort of head and neck cancer patients. Several factors were associated with an increased risk of death within 90 days of completion of radical head and neck radiotherapy. Given the potential severe acute effects and the impact on patient quality of life associated with radical head and neck radiotherapy, this information is helpful to inform treatment-related discussions with patients.

Risk assessment of the entry of canine-rabies into Papua New Guinea via sea and land routes

Canine-rabies is endemic in parts of Indonesia and continues to spread eastwards through the Indonesian archipelago. Papua New Guinea (PNG) has a land border with Papua Province, Indonesia, as well as logging and fishing industry connections throughout Asia. PNG has a Human Development Index of 0.505; therefore, an incursion of canine-rabies could have devastating impacts on human (7.5 million) and animal populations. Given the known difficulties of rabies elimination in resource-scarce environments, an incursion of rabies into PNG would also likely compromise the campaign for global elimination of rabies. A previous qualitative study to determine routes for detailed risk assessment identified logging, fishing and three land-routes (unregulated crossers ["shopper-crossers"], traditional border crossers and illegal hunters) as potential high risk routes for entry of rabies-infected dogs into PNG. The objective of the current study was to quantify and compare the probability of entry of a rabies-infected dog via these routes into PNG and to identify the highest risk provinces and border districts to target rabies prevention and control activities. Online questionnaires were used to elicit expert-opinion about quantitative model parameter values. A quantitative, stochastic model was then used to assess risk, and parameters with the greatest influence on the estimated mean number of rabies-infected dogs introduced/year were identified via global sensitivity analysis (Sobol method). Eight questionnaires - including 7 online - were implemented and >220 empirical distributions were parameterised using >2900 expert-opinions. The highest risk provinces for combined sea routes were West Sepik, Madang and Western Province, driven by the number of vessels and the probability of bringing dogs. The highest risk border districts for combined land routes were Vanimo-Green River and South Fly, driven by the number of people crossing the border and the number of dogs (with hunters). Overall, the risk posed by land routes was much higher than the risk of rabies introduction by sea routes. This study provides a foundation to develop targeted border control measures, surveillance and response strategies for canine-rabies for the highest risk routes and regions in PNG. Sensitivity analysis using the Sobol method played a key role in this study and directed further data collection to refine risk estimates. The ease of expert-elicitation using online methods demonstrates the feasibility of using such methods for animal and human disease surveillance in PNG.

The International Association of Student Surgical Societies: A brief history from 2014-2017

The International Association of Student Surgical Societies (IASSS) was founded in 2011 to link up student surgical societies from around the world. These Societies have been formed by students with an aim to promote interest in surgical education and research amongst undergraduate medical students. Their formation has been fostered by the recent realization that adequate surgical care is a neglected component of global public health.1 The insufficient number of trained surgeons is one of the many barriers to meeting global surgical needs, especially in middle- and low-income countries. This barrier is one the IASSS aims to address.2,3 Since its inauguration, the IASSS has been active in creating opportunities for undergraduate medical students across the world to explore the full spectrum of surgery.

10-year review of Africa's first student surgical society - UCT Surgical Society

The UCT Student Surgical Society is an undergraduate surgical society based at the University of Cape Town (UCT) which aims to promote surgical education amongst medical students early in their medical careers. Founded in 2006, this was Africa's first student surgical society and has been joined by other medical schools in Africa also establishing their own undergraduate student surgical societies. In this review of the first 10 years of the society, we describe its objectives, its evolution and its international role.

Twenty-four hour Holter monitoring in finishing cattle housed outdoors

INTRODUCTION

Atrial premature complexes have been reported to be the most common arrhythmia in cattle and is suspected to be secondary to systemic disease, especially gastrointestinal disease. In order to properly identify pathologic arrhythmia in cattle, the normal rhythm and arrhythmia prevalence should be defined. The objective of this study was to determine the normal heart rate, rhythm, number of ventricular premature complexes (VPCs), and atrial premature complexes (APCs) in unrestrained Angus steers.

ANIMALS

Twenty-seven client owned steers with unremarkable physical examinations and serum biochemical analyses were used.

MATERIALS AND METHODS

Twenty-four hour Holter monitors, attached by a custom-made harness, were retrospectively evaluated. Three lead electrocardiographic registrations of good quality and normal sinus rhythm were obtained from all steers in the study.

RESULTS

The mean heart rate was 66.8 bpm ± 16.4 bpm. Ventricular premature complexes were rare (noted in 14.8% of steers), and APCs were common (noted in 85% of the steers). Simple second degree AV block was observed in 18.5% of the steers.

CONCLUSION

In summary, healthy steers have rare single VPCs, although it is possible for an individual animal to have apparent more frequent VPCs. Mean heart rate varies with a diurnal pattern similar to other species. Atrial premature complexes are the most prevalent abnormality observed in feedlot steers.

High-flow oxygen in patients undergoing procedural sedation in the emergency department: A retrospective chart review

OBJECTIVE

Hypoxia is a recognised complication of procedural sedation. This study sought to determine whether there was an association between the use of high-flow oxygen delivery by a non-rebreather (NRB) mask during ED procedural sedation and decreased rates of hypoxia when compared with alternative oxygenation methods.

METHODS

Records of all procedural sedations performed over a 12 month period in an Australian tertiary ED were reviewed retrospectively. The primary outcome was whether recorded oxygen saturations fell below 90%. Specifics of the oxygen delivery method were noted and data collected included sex, age, indication for sedation, drugs and doses administered, time of day sedation was commenced and staff grade of sedationist.

RESULTS

A total of 755 procedural sedations were reviewed. Two hundred and five (27.1%) patients were administered oxygen via NRB mask from the outset of their sedation. NRB administration was associated with a statistically significant decreased rate of hypoxia (1/205 patients vs 23/550 [odds ratio: 0.112; 95% confidence interval: 0.003-0.0702]; P = 0.0090). This association remained statistically significant when adjusted for confounders.

CONCLUSIONS

This study demonstrates an association with a statistically significant reduction in hypoxia when high-flow oxygen via NRB mask is administered during emergency procedural sedation. This intervention is simple, safe and inexpensive, and we would advocate that it be evaluated further in prospective trials.